LED Display Unit Alignment Marks for High-Yield Die Bonding
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing LED display unit groups face challenges with low production efficiency and yield due to low alignment precision and increased alarm rates during die bonding, primarily caused by the traditional LED's low alignment precision as the distance between display points decreases.
Innovation Solution
The proposed solution involves a LED display unit group with a substrate that includes a pad layer, an ink layer, and an identification structure. The pad layer has pad regions and non-pad regions with metal traces, and the identification structure is positioned to overlap or not overlap with the pad regions' projections, allowing for precise alignment and identification of electronic device positions and potential defects, thereby improving die bonding efficiency and yield.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If the distance between display points is reduced to achieve higher display resolution, then the display quality is improved, but the alignment precision deteriorates and alarm rate increases
Solution Approach 1:
The patent applies preliminary action by pre-setting identification structures (alignment marks) on the substrate before the die bonding process. These identification structures enable the machine table to perform precise alignment operations, thereby maintaining high alignment precision even when display point distances are reduced. This preliminary preparation prevents alignment errors that would otherwise cause alarm rates to increase and production efficiency to deteriorate.
2Measurement precision
If the distance between display points is reduced to achieve higher display resolution, then the display quality is improved, but the alarm rate during die bonding increases
Solution Approach 1:
The identification structures are prepared in advance on the substrate, allowing the machine table to perform precise alignment before die bonding. This preliminary alignment measurement prevents misalignment errors during the bonding process, thereby reducing alarm rates and improving reliability while maintaining the reduced display point distance.
3Manufacturing precision
If traditional LED alignment methods are used, then the manufacturing process is simple, but the alignment precision is low and product yield is affected
Solution Approach 1:
The patent introduces identification structures (alignment marks) as intermediary elements between the substrate and the die bonding process. These intermediaries provide reference points for precise alignment, significantly improving manufacturing precision. While this adds some structural complexity, the use of standard identification mark patterns keeps the increase manageable, and the benefit of improved alignment precision and product yield justifies the added complexity.
Data Source
AI summary
A LED display unit group includes a substrate and an electronic device, where the substrate includes a pad layer, an ink layer and an identification structure, the pad layer is disposed on a first surface of a side of the substrate adjacent to the electronic device; the pad layer includes pad regions and a non-pad region, each of the pad regions includes multiple pads, and the non-pad region includes metal traces; and the ink layer is disposed above the pad layer; each of the multiple pads is configured to secure the electronic device and is electrically connected to the electronic device; the metal traces are configured to connect the multiple pads via the metal traces; and an orthographic projection of the identification structure on the substrate is partially overlapped or staggered with an orthographic projection of the pad regions on the substrate.